A challenge which accompanies the use of large-capacity relational databases in carrier-grade IT is massive data. To address this challenge, a system is required to provide a large capacity, high-speed access, and a high reliability mechanism. In the system, a high availability (High Availability, HA) cluster is required to reliably and effectively switch a database service to a standby server. Generally, in a dual-host mode of a disk array, an active server and a standby server transfer control information such as a heartbeat and switchover by using a heartbeat service; the heartbeat service is transmitted on hardware other than a disk array, such as an IP facility, a time division multiplexer, an optical fiber, or a serial port.
When the heartbeat service is faulty, the HA cluster is split into two or more independent individuals, instead of operating as a whole. The individuals lose contact with each other, and all consider that the other individuals are faulty. As a result, all the independent individuals contend for a shared resource, and read and write shared storage simultaneously, that is, perform a read/write operation on a disk array simultaneously, thereby resulting in data corruption, which is called split-brain. It is difficult, time-consuming and labor-intensive to recover corrupted data, and the data is very likely to be completely corrupted, which leads to unpredictable economic loss.
In the prior art, split-brain may be prevented by means of using a redundant heartbeat link, that is, a heartbeat is transferred by the Transmission Control Protocol (Transmission Control Protocol, TCP), the User Datagram Protocol (User Datagram Protocol, UDP), a serial port or the like, so as to reduce occurrences of split-brain in a scenario of active/standby setup, and ensure security of a critical resource database. The foregoing manners for transferring a heartbeat may be used simultaneously; or only one of them is used, and the rest are regarded as candidates. However, when a redundant heartbeat link is faulty, split-brain inevitably occurs.